We pin pylint to the current latest, and fix the current problems.

PyLint adds new issues every release -- this lets us choose when we get them instead of bitrotting.

The usual stuff (six, unicode carefulness, print()) plus:

• Move to incremental, versioneer had weird problems on 3.6
• im_self/self for methods
• Move to saner way of testing functions, required code changes

docker ENV has this handy syntax to let you reference the previous value of an env-var

PATH=/mystuff/bin/:${PATH}

Something like that would be nice. Or, perhaps alternatively, the ability to mark the whole environment or certain variables as pass-through. (PATH, PYTHONPATH, things like that).

Write a simple hello-world klein app that reports web statistics to statsd, and run an example with a beat-based health-check and HTTP-based check, a statsd server, a carbon server, and a graphite server which allows monitoring of the app.

In ncolony/schedulelib.py service, and ncolony/beatcheck.py service, the services need to look for an NCOLONY_CONFIG environment variable, and if one is found then to start a service that beats.

Per https://github.com/ncolony/ncolony/pull/61#issuecomment-351845310, no tox test environment needs to depend on gather, because ncolony itself depends on it.

• Explain python -m ncolony.ctl/"from ncolony import ctllib"/create JSON files options.
• Explain each field. Give thorough examples.
• Explain --messages/--config
• Show a run through of starting up a system, recovering from problems and restarting things.

(venv) => twistd -n ncolony --messages messages --config conf 2018-09-30T09:38:09-0700 [twisted.scripts._twistd_unix.UnixAppLogger#info] twistd 18.7.0 (/Users/nona/projects/ncolony_test/venv/bin/python 2.7.10) starting up. 2018-09-30T09:38:09-0700 [twisted.scripts._twistd_unix.UnixAppLogger#info] reactor class: twisted.internet.selectreactor.SelectReactor.

Good so far... but then (and right from the example here https://ncolony.readthedocs.io/en/latest/running.html#running-ncolony):

(venv) => python -m ncolony ctl add my-cat-program --cmd cat usage: main.py [-h] --messages MESSAGES --config CONFIG {restart-all,restart,remove,add} ... main.py: error: argument --messages is required

Fiddling with arguments specified in the trace doesn't seem to work.

Suggestions welcomed.

$ python -m ncolony ctl --messages /tmp/message --config /tmp/config add test --cmd date
Traceback (most recent call last):
  File "/home/mrw/.pyenv/versions/2.7.13/lib/python2.7/runpy.py", line 174, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/home/mrw/.pyenv/versions/2.7.13/lib/python2.7/runpy.py", line 72, in _run_code
    exec code in run_globals
  File "/home/mrw/src/python/ncolony/ncolony/__main__.py", line 21, in <module>
    output=sys.stdout
  File "/home/mrw/.virtualenvs/ncolony/lib/python2.7/site-packages/gather/api.py", line 200, in run
    commands[argv[0]](argv)
  File "ncolony/ctllib.py", line 212, in main
    call(ns)
  File "ncolony/ctllib.py", line 175, in call
    func(places, **results)
  File "ncolony/ctllib.py", line 72, in add
    args = [cmd]+args
TypeError: can only concatenate list (not "NoneType") to list

That's because argparse's append action allows its target value to default to None.